On the morning of the Indiana Republican primary, Ted Cruz unleashed a torrent of insults at Donald Trump after the Republican front-runner accused Cruz’s father, Rafael,
of being connected to Lee Harvey Oswald, who assassinated President John F. Kennedy. “I’m going to do something I haven't done for the entire campaign, for those of you all who have traveled with me, all across the country,” Cruz said during a press conference Tuesday. “I’m going to tell you what I really think of Donald Trump.”

With that, Cruz spewed forth all of the feelings he has presumably been bottling up since the beginning of the Republican primary race, when he was still playing nice with Trump in a transparent bid to win over his supporters:

This man is a pathological liar. He doesn't know the difference between truth and lies. He lies practically every word that comes out of his mouth. And he had a pattern that I think is straight out of a psychology textbook. His response is to accuse everybody else of lying. He accuses everybody on that debate stage of lying, and it's simply a mindless yell. Whatever he does, he accuses everyone else of doing. The man cannot tell the truth, but he combines it with being a narcissist. A narcissist at a level I don’t think this country has ever seen. Donald Trump is such a narcissist, that Barack Obama looks at him and goes, ‘Dude, what’s your problem?’ Everything in Donald’s world is about Donald. And he combines being a pathological liar, and I say pathological because I actually think Donald—if you hooked him up to a lie-detector pass, he could say one thing in the morning, one thing at noon, and one thing in the evening, all contradictory, and he'd pass the lie-detector test each time. Whatever lie he’s telling, at that minute he believes it, but the man is utterly a moron.

Cruz’s tirade came just hours after Trump accused Cruz’s father of being connected to the plot to assassinate J.F.K., citing a report from the tabloid magazine National Enquirer. “What is this, right prior to his being shot, and nobody even brings it up. They don't even talk about that. That was reported, and nobody talks about it,” Trump told the hosts of Fox & Friends on Tuesday morning. “I mean, what was he doing—what was he doing with Lee Harvey Oswald shortly before the death? Before the shooting?”

Cruz, who had to spend the weekend refuting impossible rumors that he was the Zodiac killer, convened a press conference to shoot down the story. “Now, let’s be clear, this is nuts. This is not a reasonable position. This is just kooky. And while I’m at it I guess I should admit my dad is J.F.K., he's secretly Elvis and Jimmy is buried in his backyard,” he told reporters, adding that the *Enquirer’*s C.E.O., David Pecker, was an ardent Trump supporter whose paper previously published unsubstantiated rumors that Cruz repeatedly cheated on his wife, Heidi (whose looks Trump previously mocked). “They just spread lies, blatant lies, but I guess Donald was dismayed because it was a couple weeks ago they wrote this story about JFK and Donald was dismayed that the folks in the media weren't repeating this latest idiocy, so he figured he'd have to do it himself.”

“Morality does not exist for him,” he continued, calling Trump a “bully” for suggesting that Heidi was ugly. “Bullies come from a deep, yawning cavern of insecurity. There is a reason Donald builds giant buildings and puts his name on them everywhere he goes.”

He went on with his epic takedown, saying that Trump “is cynically exploiting that anger, and he is lying to his supporters [and] will betray his supporters on every issue,” that Trump is “terrified by strong women,” that Trump happily accepted the endorsement of Mike Tyson, “a convicted rapist who served three years in prison here in Indiana for raping a 17-year-old girl,” and who “is a serial philanderer and he boasts about it. This is not a secret.”

“I want everyone to think about your teenage kids. The president of the United States talks about how great it is to commit adultery, how proud he is, describes his battles with venereal disease as his own personal Vietnam,” he added.

“And I would say to the Hoosier State, the entire country is depending on you,” he pleaded, appealing to “the good sense and good judgment” of voters. “We are staring at the abyss.”

The minutes-long speech was precisely what many anti-Trump Republicans had been waiting for from Cruz, though several pundits and commentators immediately questioned whether the rant was too late to have any practical effect. About half of primary voters have already likely cast their ballots in Indiana, which holds its primary Tuesday night and is expected to break toward Trump, giving him nearly all of its 57 delegates and setting the divisive billionaire on a glide path to the G.O.P. nomination. While Cruz held a comfortable lead going into the primary two weeks ago, he managed to lose ground to Trump in spite of—or, perhaps, because of—several strategic moves, such as tapping Carly Fiorina to be his running mate, and establishing (and breaking) an alliance with John Kasich.

As many on Twitter were quick to point out, Cruz’s increasing hostility toward Trump is a far cry from the calculated cordiality he projected just a few short months ago:

In Iowa last January, Trump regales voters with a humanizing personal anecdote about how he once bit his right index finger after mistaking it for a half-eaten French fry.

Photo: By Jerry Mennenga/ZUMA Press/Corbis.

A wax figure of “Duke” Wayne looks on in disgust as Trump strains to reach his fingers all the way around daughter Aissa Wayne’s frankly rather petite shoulder. (Fun fact: you could load the barrel of Wayne’s pistol with 14 of Trump’s pinkies.)

Photo: By Tannen Maury/EPA/Corbis.

As Trump talks straight through a lunch-hour town hall in February, hungry New Hampshire voters appear mesmerized by the five chicken-tender-like appendages radiating from his sausage-patty-size palm.

Photo: From The Washington Post/Getty Images.

At this 2005 gala, Trump, thinking quickly, uses both hands to keep wife Melania from getting a good look at the size of a single Puff Daddy hand.

Photo: By Johnny Nunez/WireImage/Getty Images.

Trump’s delicate right hand is nearly crushed by his nine-year-old daughter Ivanka’s huge, burly mitt at a 1991 event.

In Iowa last January, Trump regales voters with a humanizing personal anecdote about how he once bit his right index finger after mistaking it for a half-eaten French fry.

By Jerry Mennenga/ZUMA Press/Corbis.

A wax figure of “Duke” Wayne looks on in disgust as Trump strains to reach his fingers all the way around daughter Aissa Wayne’s frankly rather petite shoulder. (Fun fact: you could load the barrel of Wayne’s pistol with 14 of Trump’s pinkies.)

By Tannen Maury/EPA/Corbis.

As Trump talks straight through a lunch-hour town hall in February, hungry New Hampshire voters appear mesmerized by the five chicken-tender-like appendages radiating from his sausage-patty-size palm.

From The Washington Post/Getty Images.

Greeting voters in Iowa City, Trump surreptitiously compares his hand to a baby’s, a smile of satisfaction and relief slowly spreading across his face.

From Bloomberg/Getty Images.

At the 1990 grand opening of the Trump Taj Mahal Casino Hotel in Atlantic City, wee hands try to summon a genie from a giant lamp. “It’s the motion,” Trump gamely jokes.

An interesting optical illusion: Trump’s left hand is actually in the foreground of the picture!

By Chris Cassidy/Getty Images.

More ugly politics in South Carolina: Trump is forced to refute rumors, traced back to the Cruz campaign, that his fingers aren’t long enough for Christian prayer.

By Andrew Cowan/Scottish Parliament/Getty Images.

Trump pretends to enjoy a pork chop on a stick at the 2015 Iowa State Fair, probably the one place on Earth where people won’t mistake a pork chop on a stick for Trump’s third hand.

By Win McNamee/Getty Images.

In costume with actress Megan Mullally at the 2005 Emmys, Trump wows an audience of hardened entertainment professionals by wrapping his fingers nearly all the way around a pitchfork.

By Mathew Imaging/FilmMagic/Getty Images.

Some pundits have attributed candidate Trump’s hawkishness to the fact that, even though his fingers have as many joints as a normal man’s, they remain at least an inch short of being able to form a proper peace sign.

From The LIFE Picture Collection/Getty Images.

Nothing much to say about the fingers in this picture; just curious why Trump’s “anus mouth” face hasn’t also become a thing.

From CNBC/Getty Images.

To this day, clubhouse attendants maintain that Trump had to be outfitted with a Babe Ruth Jr. Youth League glove for this 1991 appearance at Yankee Stadium.

From the Donaldson Collection/Michael Ochs Archives/Getty Images.

At this 2005 gala, Trump, thinking quickly, uses both hands to keep wife Melania from getting a good look at the size of a single Puff Daddy hand.

By Johnny Nunez/WireImage/Getty Images.

Trump’s delicate right hand is nearly crushed by his nine-year-old daughter Ivanka’s huge, burly mitt at a 1991 event.